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Jon Prouty
10-15-2014, 10:53 PM
Whoa - close one tonight. I was roughing out some bowls, and decided at the last minute to put down my cage. Halfway through the next bowl, it came off of the worm screw. It's smacked against the cage and lodged against the tool rest. I was taking too big of a cut. I drilled the hole too large because I'm an idiot. I duon't know for sure if it would have hit me but I do know I would have needed new underpants if that cage wasn't down.

Jon Prouty
10-15-2014, 10:57 PM
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I also didn't have a good clean face for the jaws to sit against. Multiple errors in judgement. Be safe out there and happy turning.

Reed Gray
10-16-2014, 12:44 AM
It doesn't look like the tailstock was engaged. That does help keep things in place. Also, it is best to have a dead flat spot to go up against the jaws for a screw chuck.

robo hippy

Thomas Canfield
10-16-2014, 12:57 AM
Ditto what Reed said plus:

1. I use a large (2-7/8 to 3-1/8") Forstner bit to get a flat spot for chuck face with wirm screw
2. I also will add thin CA to drilled pilot hole in wet wood to strengthen to help prevent tear-out of threads
3. Always use the live center in tail stock, even if it has a pad attached, to maintain pressure on block when roughing. Remove only to finish tenon and add dimple for center later. (Hate to say how many times just cleaning up tenon can be a problem).

Jon Prouty
10-16-2014, 1:08 AM
You guys are right - no tail stock support either. I should go back to a faceplate for my own safety for a while.

JP

Jon Prouty
10-16-2014, 1:12 AM
BTW - I tossed this piece as I was feeling too much bad juju coming from it. I wasn't going to risk another attempt on this one even with a faceplate.

JP

Thom Sturgill
10-16-2014, 7:09 AM
Personally, I like the method Ashley Harwood has been teaching:
1) start between centers bowl mounted such that base is at headstock
2) clean & balance piece and adjust if needed for better grain orientation
3) flatten TOP and cut recess for largest jaws.
4) reverse to chuck w recess
5) shape outside and tenon
6) reverse to chuck w tenon
7) hollow

Kyle Iwamoto
10-16-2014, 1:17 PM
Wow, and I thought I was the only one who actually uses the cage. Good thing you had it down.

A recent article in American Woodturner said that if you paint your cage flat black, it makes it a LOT easier to "see" through the cage. I did it and it works great.

Yeah, use your tailstock, especially when roughing.

Marty Tippin
10-16-2014, 2:44 PM
I start bowls between centers, using a 2" screw-on drive center from Stubby Lathe (marketing PDF document is here http://stubbylatheusa.com/Convertible_Drive_Center.100.pdf) and really like it a lot. Combined with a cup center on the tailstock, I have a lot of flexibility to re-orient the piece as needed during turning. Other than a couple of times when working in punky, soft wood (that I probably shouldn't have been using anyway), I've not had any issue with the spurs tearing out, and so far (knock on compressed fiber board), I haven't had a piece unmount itself from the lathe at all.

The one time I tried using a screw center, the threads tore out within a minute or two and the piece would have gone flying, were it not for the tailstock. That was enough for me and I haven't used the wood worm screw since.

The procedure Thom outlined seems like way too much work to me - reversing the piece two times - but maybe I'm missing some benefit to doing things that way. For now, I simply rough shape and turn a tenon (piece is oriented with the foot toward the tailstock), then reverse and chuck, do final shaping and hollowing.

Pat Scott
10-16-2014, 3:00 PM
I use a worm screw for all my roughing, but I always use the tailstock too. If I take too big of a cut, or if the wood is soft, the only thing that happens is the hole strips out. If that happens, I remove one of my plywood spacers, drill the hole a bit deeper, and try again.

You wouldn't have had any problems if the tailstock were in place.

Jeff Wayne
10-16-2014, 5:28 PM
Kudos to you for being egoless enough to post up. Maybe others can learn . . . from the remote safety of our computer screens.

Thanks.